Turbine rotor construction



Oct. 15,19 7

E. c. CURRY TURBINE ROTOR cous'mucuou Filed April 18-. 1952 HIS ATTORNEY United States Patent TINE ROTOR CONSTRUCTION Application April 18, 1952, Serial No. 283,100

2 Claims. (Cl. 253-77) This invention relates to turbine rotor construction and more particularly to that type of turbine rotor which is provided with a hub and blading formed separately and adapted to be attached thereto.

It is an object of the invention to provide a form of binding and hub which is easily manufactured and assembled.

Another object of the invention is to providea form of blade root which will properly support the blade upon the hub.

Other objects and advantages of the invention will be in part referred to and in part evident from the following description.

In the drawing in which similar parts are designated by similar reference characters,

Figure 1 shows a fragment of a turbine hub shown in side elevation and partly in central section indicating the method of which the turbine blades are held in place therein according to a preferred embodiment of the invention,

Fig. 2 is a transverse axial section across aportion of the hub and blading shown in Figure 1, showing more particularly the blade root section,

Fig. 3 is a bottom view of the root portion of the blade, the profile of the blade portion being indicated in broken lines;

Fig. 4 is a perspective view of the blade root and a portion of the blade portion proper; and

' Figure 5 is an enlarged scale view in longitudinal section of the lower end of the blade root showing more particularly the resilient finger construction.

In Figure l is shown at a broken away portion of a turbine hub upon which are mounted a plurality of turbine blades 12 each of which is provided with a blade portion 14 and a root portion 16. In the periphery of the hub 10 is formed a continous' circumferential slot 18 to receive the root portion 16 of the blade 12 and within which the blade is adapted to be held rigidly. For this purpose the slot 18 is provided with two sets of laterally extending shoulders 20 adapted to engage complementary outwardly extending shoulders 22 formed on the root portion 16 of the blades 12.

As the blades 12 lie in position in the slot 18 it is desired that they should be held as rigidly as possible with the faces of the shoulders 20 pressing against the faces of the shoulders 22. To this end there is provided a pair of spring members 24 formed at the base of the root section 16 and adapted to press against the bottom of the slot 18 at a central accurately machined path 26. The spring fingers 24 are formed by an aperture 28 preferably bored close to the bottom of the root 16 and a slot 30 cut through the wall thus formed to the aperture 28.

As the blades are pressed with considerable force into the slot 18 in the usual well known manner the spring fingers 24 are flexed to provide pressure tending to force Patented Oct. 15, 1957 the blade 12 radially outward forcibly keeping the I applied inwardly on the blade 12 its motion in the slot is limited.

I claim:

1. Turbine rotor construction comprising a hub portion having a continuous peripheral slot of substantially uniform cross section and extending radially inward, 'a blade having a root portion extending inwardly into said slot, said root portion having lateral oppositely extending shoulders rigid with respect to each other and intermediate the ends of said root portion, complementary shoulders in said slot having faces for engagement with and overhanging the first said shoulders, and a spring for maintaining such engagement including a pair of resilient members at the end of said root portion and pressing against the bottom of said slot, said resilient members being formed integrally with said root portion, said lateral shoulders of said root portion engaging the radially inner faces of said overhanging complementary shoulders of said slot, and that part of said root portion including said resilient members from said engaging faces of said lateral shoulders radially inward to the end of said root portion being of greater radial length than the portion of said slot radially inward from the corresponding said engaging faces of said complementary shoulders radially inward to the bottom of said slot where said resilient members press as aforesaid.

2. Turbine rotor construction comprising a hub portion having a continuous peripheral slot of substantially uniform cross section and extending radially inward, a blade having a root portion extending inwardly into said slot,

,said root portion having lateral oppositely extending shoulders rigid with respect to each other and intermediate the ends of said root portion, complementary shoulders in said slot having faces for engagement with and overhanging the first said shoulders, and a pair of fingers formed integrally with and at the radially inward end of the root portion extending toward each other and adapted to be sprung by pressure against the bottom of said slot, said lateral shoulders of said root portion engaging the radially inner faces of said overhanging complementary shoulders of said slot, and that part of said root portion including said fingers from said engaging faces of said lateral shoulders radially inward to the end of said root portion being of greater radial length than the portion of said slot radially inward from the corresponding said engaging faces of said complementary shoulders radially inward to the bottom of said slot where said fingers press as aforesaid.

References Cited in the file of this patent UNITED STATES PATENTS 

